Hickey: Capturing a River—Arrr!

Geologists actually call it river piracy, writes Hannah Hickey, when one stream takes over another. Presumably, the geoscientists don’t yell “Shiver me timbers!” when they see it, but it’s hard to know because, Hannah writes, it happens infrequently. University of Washington researchers documented the rare event, though, and Hannah tells why and how it happened. @hickeyhimage: NASA